Step stool



FIG. 1 is a perspective view of the step stool, incorporating the new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a right side elevational view thereof; and

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a top view of the step stool; and,

FIG. 7 is a bottom view of the step stool.

The broken lines shown in the drawings are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for the step stool, as shown and described. 